The latest update for cherry blossom forecast indicates Tokyo will see a start of cherry blossom around March 20, which is forecasted as the earliest location in Japan. Usually, a week after the start of the cherry blossom is considered to be the peak, which means the peak of cherry blossom in Tokyo will be around March 27.

The start of cherry blossom forecasted (again, the peak of blossom is usually 7-9 days after the start of the blossom)
Osaka: March 26
Nagoya: March 23
Fukuoka: March 21
Sapporo: April 23
Sendai: April 3
Aomori: April 15
Hiroshima: March 21
Kochi: March 24
Kagoshima: March 27